The purpose of this study is to determine the incidence of sinusitis in mechanically ventilated burn victims and to examine if the presence of inhalational injury increases the likelihood of developing sinusitis. The authors hypothesize that the incidence of sinusitis will be increased in burn victims who have concomitant inhalational injury. A retrospective chart analysis was performed on all patients who were admitted to the Nathan Speare Regional Burn Treatment Center over a 24-month time frame. Patients who were mechanically ventilated for greater than 24 hours were then selected, resulting in a total of 137 patients for analysis. Multiple variables including number of days on mechanical ventilation, presence of confirmed inhalational injury by bronchoscopy, and method of diagnosis were examined. Of 137 patients, a diagnosis of sinusitis was made in 32 patients (23%). In patients with sinusitis, 87.5% had inhalational injury confirmed with bronchoscopy, compared with only 33.3% of patients without sinusitis (P < .01). Rates of nasotracheal/nasogastric intubation, nasoenteric feeding, and length of mechanical ventilation before sinusitis diagnosis were not significantly different. Patients with sinusitis were found to have suffered inhalational injury at a significantly higher rate than those who did not develop sinusitis. This suggests that inhalational injury is a significant risk factor for developing sinusitis.